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{{condense|date=November 2011}}
A '''database''' is an organized collection of [[data]] for one or more purposes, usually in digital form. The data are typically organized to model relevant aspects of reality (for example, the availability of rooms in hotels), in a way that supports processes requiring this information (for example, finding a hotel with vacancies). This definition is very general, and is independent of the technology used.
The term "database" may be narrowed to specify particular aspects of organized collection of data and may refer to the logical database, to physical database as data content in [[computer data storage]] or to many other database sub-definitions.
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=====Network model=====
{{Main|Network model (database)}}
In this model a hierarchical relationship between two record types (representing real-world entities) is established via the ''set'' construct. A set consists of circular [[linked list]]s where one record type, the set owner or parent, appears once in each circle, and a second record type, the subordinate or child, may appear multiple times in each circle. In this way a hierarchy may be established between any two record types, e.g., type A is the owner of B. At the same time another set may be defined where B is the owner of A. Thus all the sets comprise a general [[directed graph]] (ownership defines a direction), or ''network'' construct. Access to records is either sequential (usually in each record type) or by navigation in the circular linked lists.
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